chris_stampe

I just finished installing my ltx8 on a freshley rebuilt motor. I have stock 550 primaries and 1600 secondaries. I figured that I wont be using my secondaries to break the motor in, so I was just going to use the base map for break in. Then throw it on the dyno and tune it for the 1600s. Well I was trying to put some miles on it last night. My problem is that my exhaust temps are way too high. My turbo and manifold are glowing red. I have an old O2 sensor so I dont really trust that. It says I am running 16-17, which made sense that it was running lean and therefore too hot. So I richened out the rpmwot map, and the rpmcrs map by 20%, didnt change the o2 reading. then by 40%, still didnt change the reading but i started getting black smoke, which made me think it was rich. I even tried 50%, but then it ran like **** and blew a lot of smoke. I also tried adjusting the load map by just increasing the ms amounts, but that just made more black smoke. Even with it rich the turbo is still glowing. I took out my spark plugs and they were black, not white like if it was lean. What could be causing my high exhaust temps? Ignition? Please help if you have any ideas or suggestions. I will call microtech on monday and see what they have to say, but I usually get my best advice off here, not over the phone from manufacturers.
Chris

chris_stampe

Ok, I am going to just keep posting about this in hopes that someone smart replies. I know that adjusting the load map isnt a great idea, but I did it anyways and richened it out before my secondaries open, and leaned it out when they open. I took the car for a short spin, and the manifold wasnt glowing at least this time. I also have an old school wideband that is reading pretty consistent 10-11 afrs. Well since it was going ok, I decided to see what the transition was like when my secondaries opened up. I have the %stage at 95, the revstg at 2500 and then to have them come on at 0 psi. So anytime im over 2500 and hit boost they should come on (so bassically anytime I hit boost). Well the transition is rough as **** and it just backfires and hesitates when the secondaries are on. I suppose I need to lean it out more then. Is it ok to be using the load map to compensate for different sized injectors or do you need to use the matrix tables to get a smooth transition?

Turbo Timmy

are you sure the timing is right?

chris_stampe

nope im not sure, but it was at 10*, and also advanced when i reved it when i started it, and I didnt touch the timing maps.

Infini IV

It's not abnormal to have a glowing turbo manifold and turbo... Are you using an EGT gauge to measure the exhaust temps, or just assuming it's a little too hot?

As for the stumble when the secondaries come online... did you take out some fuel to compensate for the secondaries opening at 2500rpm and 0psi? Remember, even though you have adjusted the %stage, it might still be too much fuel at that load point, so you might have to lean it out a bit right around the transition point.

chris_stampe

yes i leaned it out a **** load. And my manifold used to glow, but not like this. Im pretty sure my load maps were just too lean for the porting and the t04 that i have. I dont have an egt though.

Crusader_9x

it is normal (in my experinces) for a rotary to make the manifold turbo and some of the downpipe glow red. dont owrry about it. some of the combustion is still taking plac ein the exhaust , this is why rotaries can run such big turbos.

chris_stampe

Ok, It just never did this before my rebuild/porting/microtech. But I did wrap my turbo header, so maybe that is making it retain more heat. My manifold used to glow, but not the turbo. I will post some pics just so u guys can see. Its ******* cool, but kinda scary.

LT8TurboII

iTrader: (2)

I wouldn't say it would be normal for the exhaust/turbo to glow when driving under low boost/low speed. When you are flogging on a car, its possible.

Check you timing.

RETed

EXCESSIVELY rich fuel mixtures will also skyrocket EGT's.
It's the excess fuel burning in the exhaust pipes that causes the high EGT's, and it looks like a lean condition.

This is why I also run a narrow-band AFR gauge - that'll automatically tell you it's a rich high EGT condition and not a lean high EGT condition.


-Ted

chris_stampe

^ Good call. I think that it was a combination of a few degrees off with my timing and the fact that I am running about high tens and low eleven AFRs at most every rpm/load. Thanks for the help guys the car has successfully made it to the dyno....and fucked up a honda cbr 600 on the way there. Left him in a nice cloud of black smoke.

igottafc

iTrader: (6)

did you turbo stop glowing?

chris_stampe

yea now it only glows under boost. I had my ignition timing off by 5 degrees retarded and it was runnin hella rich.